CentOS - Aug 2018 - Mail has quit working

> Date: Monday, August 27, 2018 09:57:01 -0400
> From: TE Dukes <tdukes at palmettoshopper.com>
>
>> From: CentOS [mailto:centos-bounces at centos.org] On Behalf Of
>> centos--- via CentOS
>> Sent: Monday, August 27, 2018 9:31 AM
>> 
>> On 08/27/2018 09:05 AM, TE Dukes wrote:
>> > 
>> > 
>> > Thanks again! I still think it's a mail issue. I can't get
mail
>> > using usermin either.
>> > 
>> > Think I'm going to remove the TLS stuff from postfix main.cf
>> > that I added yesterday and retry.
>> 
>> If I missed this further up thread my apologies - is SELinux
>> enabled and are there any relevant exceptions being logged?
> 
> Pretty sure SELinux is turned off unless it got turned on without my
> knowledge through an updtate/upgrade.
> 
> I removed the TLS lines from main.cf I added last night and
> remotely did a reboot from here at work.
> 
> Mail is again working!! I am skeptical to mark this thread solved
> as I thought it was solved back in July.
> 
> I think, removing my ISP's DNS servers from resolve.conf was the
> fix, could be removing IPV6 from etc/hosts. Might put it back in
> just to see.
> 
As I indicated earlier, removing those lines from your postfix config
will have no impact on your ability to reach your roundcube instance.

Unlike the windowz world, you mostly don't need to "reboot" a
machine
after making changes to a service (e.g., your postfix config change).
An unnecessary reboot can bring in many issues so makes debugging a
problem difficult. Instead, restart the service in question (often a
reload is all that's needed, but a service restart generally doesn't
hurt in a single/lower user environment).

Unless you are VPN-ing (or equiv) my sense is that you are currently
getting to your mail (roundcube) from outside your network. Earlier,
when it wasn't working, my sense was that you were inside. If that's
true you can't really tell if your issue has been resolved as you are
coming at things from different network directions.

> -----Original Message-----
> From: CentOS [mailto:centos-bounces at centos.org] On Behalf Of Richard
> Sent: Monday, August 27, 2018 10:16 AM
> To: CentOS mailing list
> Subject: Re: [CentOS] Mail has quit working
> 
> 
> > Date: Monday, August 27, 2018 09:57:01 -0400
> > From: TE Dukes <tdukes at palmettoshopper.com>
> >
> >> From: CentOS [mailto:centos-bounces at centos.org] On Behalf Of
> >> centos--- via CentOS
> >> Sent: Monday, August 27, 2018 9:31 AM
> >>
> >> On 08/27/2018 09:05 AM, TE Dukes wrote:
> >> >
> >> >
> >> > Thanks again! I still think it's a mail issue. I
can't get mail
> >> > using usermin either.
> >> >
> >> > Think I'm going to remove the TLS stuff from postfix
main.cf
> >> > that I added yesterday and retry.
> >>
> >> If I missed this further up thread my apologies - is SELinux
> >> enabled and are there any relevant exceptions being logged?
> >
> > Pretty sure SELinux is turned off unless it got turned on without my
> > knowledge through an updtate/upgrade.
> >
> > I removed the TLS lines from main.cf I added last night and
> > remotely did a reboot from here at work.
> >
> > Mail is again working!! I am skeptical to mark this thread solved
> > as I thought it was solved back in July.
> >
> > I think, removing my ISP's DNS servers from resolve.conf was the
> > fix, could be removing IPV6 from etc/hosts. Might put it back in
> > just to see.
> >
> 
> As I indicated earlier, removing those lines from your postfix config
> will have no impact on your ability to reach your roundcube instance.
> 
> Unlike the windowz world, you mostly don't need to "reboot" a
machine
> after making changes to a service (e.g., your postfix config change).
> An unnecessary reboot can bring in many issues so makes debugging a
> problem difficult. Instead, restart the service in question (often a
> reload is all that's needed, but a service restart generally
doesn't
> hurt in a single/lower user environment).
> 
> Unless you are VPN-ing (or equiv) my sense is that you are currently
> getting to your mail (roundcube) from outside your network. Earlier,
> when it wasn't working, my sense was that you were inside. If
that's
> true you can't really tell if your issue has been resolved as you are
> coming at things from different network directions.
> 
The mail in question is system mail sent via cron. I access it from both
inside the network and outside. Due to being on a dynamic ip, I can't send
mail to the outside but I can receive it.

Again, really appreciate the help!!

Added back the IPV6 to /etc/hosts a couple days ago for grins and giggles.
No longer getting IPV6 errors in logwatch for bind. Everything working.

I think removing my ISP's nameservers from /etc/resolv.conf was the fix.
They have been in there forever so still have my fingers crossed.

Again, many thanks!!